<!DOCTYPE html>
<html>

<head>
<meta charset="UTF-8">
<style>
@page {
    size: 400pt 300pt;
    margin: 50pt;
}

html {
    font-family: sans-serif;
    font-size: 14pt;
    line-height: 16pt;
}

body {
    outline: thin solid rgb(0, 0, 0, 0.25);
}

img {
    width: 50%;
    height: 120pt;
    margin-bottom: 10pt;
    outline: 2pt solid green;
}
</style>
</head>

<body>
    <img src="non-existing.png" alt=""><br>
    <img src="non-existing.png" alt="Alternate text">
</body>

</html>
